Synthesis of Furans and Pyrroles from 2‐Alkoxy‐2,3‐dihydrofurans Through a Nucleophilic Substitution‐Triggered Heteroaromatization

• DOI: 10.1002/adsc.201500993
• Publication Date: 2016-02-18T19:52:44Z
• Authors: Changhui Liu; Li Zhou; Wenbo Huang; Man Wang; Yanlong Gu
• Keywords: Substitution reaction; Pyrrole; Furan

Abstract An effective method to synthesize α‐functionalized furan and pyrrole derivatives was developed using 2‐alkoxy‐2,3‐dihydrofurans as modular precursors. This protocol featured a previously unreported tandem nucleophilic substitution/heteroaromatization reaction. Nucleophiles such indole, α‐oxoketene dithioacetal, trimethoxybenzene, dimethoxynaphthalene can react readily with afford five‐membered ring heterocycles in the presence of acid catalysts, copper bromide iron chloride. The mechanism reaction also discussed, which first step, substitution, is key triggering succeeding heteroaromatization. be extended synthesis dihydrothiophenes. magnified image